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In Xinjiang, China, traditional handmade cheese is made from fresh milk under natural environmental conditions and is a common fermented dairy product in the region. Due to differences in production methods between regions, the research conducted on the bacterial diversity of traditional handmade cheese is not comprehensive. Hence, little is known about the relationship between bacteria and cheese quality. Therefore, in this study, cheese samples from Tarbagatay Prefecture, Xinjiang, were chosen for investigation. The bacteria in 17 cheese samples were analyzed by sequencing 16S rRNA using Illumina MiSeq technology. The results showed that there were two dominant bacterial phyla and six dominant bacterial genera in the cheeses. Of these, Lactobacillus and Lactococcus displayed the most significant positive correlation with cheese quality. This study provides data to support the improvement of traditional cheese quality via microbial diversity and lays a foundation for the industrialization of traditional cheese production., Traditional cheese of Xinjiang, China, has a long history and the consumption demand is also increasing. In recent years, people pay more and more attention to the quality and microbial diversity of Xinjiang traditional cheese, which also contains a variety of microbial resources. The results showed that the bacteria in Xinjiang traditional cheese were rich and diverse, and the core dominant genera were Lactobacillus, Streptococcus, Lactococcus, Staphylococcus, Enterococcus, and Acetobacters. This study provides a basis for the industrialization of traditional fermented dairy products.

Cheese is a typical handcrafted fermented food in Kazak minority from the Uighur Autonomy Region in China and Central Asia. Among the microbial community that is responsible for Kazak cheese fermentation, yeasts play important role in flavor formation during ripening. To develop ripening cultures, we isolated 123 yeasts from 25 cheese products in Kazak, and identified 87 isolates by the D1/D2 domain of the large subunit rRNA gene sequence. Pichia kudriavzevii was the dominant yeast in Kazak cheese, followed by Kluyveromyces marxianus and Kluyveromyces lactis. Of these, the ability to exhibit enzyme of dominant isolates and contribution to the typical flavor of cheeses was assessed. Enzyme producing yeast strains were inoculated in Hazak cheese‐like medium and volatile compounds were identified by head space solid phase micro extraction coupled to gas chromatography and mass spectroscopy. Pichia kudriavzevii N‐X displayed the strongest extracellular proteolytic and activity on skim milk agar and produced a range of aroma compounds (ethanol, ethyl acetate, 3‐methylbutanol, and acetic acid) for Kazak cheese flavor, could be explored as ripening cultures in commercial production of Kazak cheeses.

Two improvement measures pointed to the past error to calculate b-values have been proposed: (1) adopt seismic moment magnitude MW which is the uniform absolute magnitude scale; (2) discard the magnitude point in which some earthquakes are missing, then compute the b-value using least square method to fit the data. Therefore b-value is more accurate. The b-values all approach to 1.0 for three sets of various precision and sources. The earthquake occurrence periods of great earthquakes for coming 50~100 year (extend 1~2 magnitude) have been computed using 13 years recent earthquake observation data and fix b=0.85. The results demonstrate that the earthquake occurrence periods with magnitude greater and equal to 6 and 7 are well consistent with that which are calculated from the data of 100 years historical earthquakes. So, the extension is reliable.